1. Field of the Invention
This invention relates generally to an uninterrupted power supply (UPS), more particularly, to an improved ON-LINE UPS, which is capable of avoiding electrical shock in replacement of battery when the civil power is under supply and regulating output voltage in spite of changes in input voltage, combined with an appending function of controlling switches from far end by means of detecting ring signal.
2. Description of the Prior Art
An average OFF-LINE UPS is characterized that when the civil power is supplied normally, the output voltage will change subject to change of the input voltage through a relay to probably mangle components in the following stages.
A conventional ON-LINE UPS is to charge a battery through a transformer and a rectifying/charging device or a single rectifying/charging device when the civil power is applied so that the charging voltage of the battery will be varied according to the input rectified voltage to probably mangle the battery and shorten lifetime thereof; and, because the charging circuit is coupled directly with the civil AC power, a user may be electrically shocked when replacing the battery.
Nevertheless, so far, not yet an OFF-LINE or an ON-LINE UPS has been applied in an unmanned relay station for electric power management controllable from far end by availing itself of an existing telecommunication device from which the concept of this invention stems. In view of the demand and after years of constant effort in research, the inventor of this invention has consequently developed and proposed this improved mechanism pertaining to the subject matter.